<template>
  <div class="nav-bar"  :class="{'is_fixed':isFixed}">
    <div class="container">
      <div class="pro-title">{{title}}</div>
        <div class="pro-param">
          <a href="javascript:;">概述</a><span>|</span>
          <a href="javascript:;">参数</a><span>|</span>
          <a href="javascript:;">用户评价</a>
          <slot name="buy"></slot>
        </div>
    </div>
   
  </div>
</template>

<script>
export default {
   name:'nav-bar',
   props:{
    title:String
   },
   data() {
     return {
       isFixed:false
     }
   },
   mounted() {
      window.addEventListener('scroll',this.initHeight)
   },
   methods: {
     initHeight(){
       let scrollTop=window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop
     this.isFixed=scrollTop > 152 ? true : false;
     }
   },
   destroyed() {
      window.removeEventListener('scroll',this.initHeight,false)
   },
}
</script>

<style lang='scss' scoped>
  @import './../assets/scss/config.scss';
  @import './../assets/scss/mixin.scss';
  .nav-bar{
    z-index:10;
    height: 70px;
    line-height: 70px;
    border-top: 1px solid #353535;
    background-color: #ffffff;
    box-shadow: 0 5px 5px #cccccc;
    &.is_fixed{
      position: fixed;
      top: 0;
      width: 100%;
    }
  }
  .container{
    @include flex();
    .pro-title{
      font-size: 18px;
      font-weight: bold;
    }
    .pro-param{
      font-size: 14px;
      span{
        margin: 0 10px;
      }
      a{
         color: $colorC;
        
      }
    }
  }
</style>